The leader of Britain's main eurosceptic party has hailed "wise" Swiss voters for backing curbs on EU immigration, saying it would encourage others across the continent.

Nigel Farage, the head of the UK Independence Party, said Switzerland had stood up to "bullying" from Brussels and that it was "not a matter of race but of space."

"This is wonderful news for national sovereignty and freedom lovers throughout Europe," said Farage, who is a member of the European parliament (MEP).

"A wise and strong Switzerland has stood up to the bullying and threats of the unelected bureaucrats of Brussels."

Final results from a referendum showed that 50.3 per cent of Swiss voters had backed the "Stop Mass Immigration" proposal pushed by right-wing populists, threatening to ignite a row with Brussels.

UKIP has led calls for similar calls for a cap on immigration, a touchy issue in Britain since Bulgarians and Romanians were given full rights on January 1 to free movement within the European Union.

"It is a great thing to be welcomed that the Swiss people now have the freedom to decide the number and skill level of the people who they wish to invite to work or stay in their country," Farage added.

"It is not a matter of race but of space, of numbers and of skills," he said.

UKIP has no lawmakers in the British parliament but threatens to sap vital votes from Prime Minister David Cameron's Conservative party in Britain's next general election in May 2015.